Gauges for inserting dental implants

ABSTRACT

After retraction of the periostium a rectangularly shaped channel, having a configuration equal to the shape of the implant, is cut in the jawbone beneath the ridge crest. The channel is checked with a gauge having a shape substantially the same as the implant but having slightly smaller dimensions. The channel is then enlarged and again checked with another gauge, slightly larger than the first. The process is repeated until the channel is of the proper size. A rectangularly shaped implant having two spaced apart substantially parallel vertical side walls is then inserted into the channel so that the entire implant is below the top level of the bone. The walls of the implant are then cammed outwardly with the use of screw means so as to press against the walls of the channel to secure the implant in place. After the bone and other tissue has grown around the implant and over the top thereof, the plug in the tapered hole at the middle of the implant is removed and a post is screwed therein to which a tooth is molded.

This is a division of prior application Ser. No. 792,522 filed May 2,1977, now U.S. Pat. No. 4,177,562, Dec. 11, 1979.

BACKGROUND OF THE INVENTION

The present invention is directed toward a dental implant and a methodfor inserting the same and more particularly toward a dental implant andmethod which allows for substantially more accurate implanting withoutthe trauma normally experienced with known implants.

Dental implants for replacing lost teeth have been known for some timeand have been increasing in popularity over the past several years.Unfortunately, most known implants have met with only moderate success.

Most of the dental implants presently in use today are comprised of awedge shaped blade having a sharp edge. The implant is inserted bytapping the blade into a prepared groove in the jawbone of the patient.Thereafter, an artificial tooth structure is secured to the supportportion which extends upwardly from the blade. It should be readilyapparent that driving the blade into the bone causes trauma and it isbelieved that this is one of the main reasons for the failure of theimplant. Examples of these prior implants are shown, for example, inU.S. Pat. Nos. 3,465,441; 3,849,888; 3,977,081 and numerous others.

Devices have been proposed which are intended to be implanted withoutthe use of the above described technique. For example, U.S. Pat. Nos.3,866,321 and 3,881,251 show a device which includes a blade apparentlyhaving a flat bottom portion. According to the patents, a narrow cut isfirst made in the jawbone structure and the blade is then fitted intothe cut. However, in order to hold the blade in place, a plurality ofinjections are formed on each side thereof which force themselves intothe side walls of the cut thereby, for all intents and purposes,creating the same trauma that is created in the previously describeddevices.

A further attempt to overcome the problems of the prior implants isshown in U.S. Pat. No. 3,708,883. In accordance with this patent, acylindrical bore is first drilled into the jawbone and a substantiallycircularly shaped implant having external threads is then screwed downinto the bore. The lower end of the implant is split so that it can bespread apart with the use of a screw which extends upwardly through theimplant. While this device would appear to overcome some of the abovedescribed disadvantages of the prior art, it has many disadvantages ofits own. Of primary significance is the fact that the implant cannot bepositioned totally beneath the upper level of the bone because of thescrew which extends upwardly from the device.

SUMMARY OF THE INVENTION

The present invention overcomes all of the above described problems ofthe prior art. According to the invention, a rectangularly shapedchannel having a size substantially equal to the shape of the implant iscut in the jawbone beneath the ridge crest. The channel is checked witha gauge having a shape substantially the same as the implant but havingslightly smaller dimensions. The channel is then enlarged and againchecked with another gauge, slightly larger than the first. The processis repeated until the channel is of the proper size. A rectangularlyshaped implant having two spaced apart substantially parallel verticalside walls is then inserted into the channel so that the entire implantis below the top level of the bone. The walls of the implant are thencammed outwardly with the use of screw means so as to press against thewalls of the channel to secure the implant in place. After the bone andother tissue has grown around the implant and over the top thereof, theplug in the tapered hold at the middle of the implant is removed and apost is screwed therein to which a tooth is molded.

BRIEF DESCRIPTION OF THE DRAWINGS

For the purpose of illustrating the invention, there is shown in theaccompanying drawings forms which are presently preferred; it beingunderstood that the invention is not intended to be limited to theprecise arrangements and instrumentalities shown.

FIG. 1 is a perspective view of an implant constructed in accordancewith the principles of the present invention and showing the variousparts associated therewith in an exploded form;

FIG. 2 is a cross-sectional view taken along the line 2--2 of FIG. 1;

FIG. 3 is a view similar to FIG. 1 showing a second embodiment of theinvention;

FIG. 4 is a view similar to FIG. 1 showing another embodiment of theinvention;

FIG. 5 is a view similar to FIG. 1 showing a still further embodiment ofthe invention;

FIG. 6 is a cross-sectional view taken along the line 6--6 of FIG. 5;

FIG. 7 is a perspective view of a gauge tool used with the presentinventive method;

FIGS. 8, 9 and 10 illustrate the various stages in implanting one of thedental implants of the present invention, and

FIG. 11 is a perspective view of an angled post which may be used withthe present invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the drawings in detail wherein like reference numeralshave been used throughout the various figures to designate likeelements, there is shown in FIG. 1 a dental implant constructed inaccordance with the principles of the present invention and designatedgenerally as 10.

Implant 10 is substantially rectangularly shaped and includes a pair ofside walls 12 and 14 and a top wall 16. Each side wall, such as sidewall 12 for example, is preferably divided into a plurality of sectionssuch as shown at 18, 20 and 22. The division of wall 12 into the parts18, 20 and 22 is made by cutting through the wall vertically from thebottom to a point adjacent the top wall 16 such as shown at 24 and 26. Aplurality of holes 28 are formed in the walls 12 and 14. These holesallow the bone and other tissue to grow around the implant to maintainthe same securely in place as is well known in the art.

Located on the top wall 16 adjacent the center thereof is an upwardlyextending tubular collar 30. On either side of the collar 30 and atapproximately midpoint of the wall sections 18 and 22 are threadedopenings 32 and 34. As shown in FIG. 1, a screw such as screw 36 isadapted to be screwed into threaded opening 32 and a screw 38 is adaptedto be screwed into the threaded opening 34. Similarly, either anelongated plug 40 having a screw thread 42 at the base thereof or amounting post 44 having a screw thread 46 at the base thereof is adaptedto be screwed into the opening formed by the collar 30.

As shown best in FIGS. 1 and 2, sections 18 and 22 of the side wall 12are relatively thin metal walls which are spaced from similar parallelwall sections 48 and 50 of the side wall 14. On the other hand, section20 has a thickness which extends between the walls 12 and 14.

Referring to FIG. 2, it can be seen that a bore 52 is formed verticallythrough the collar 30, top wall 16 and into the interior of the wallsection 20. The bore 52 is tapered slightly upwardly and outwardly andincludes screw threads 54 at the bottom thereof. Bore 52 terminatesshort of the bottom of the wall section 20 thereby leaving a partialbottom wall 56.

As is also shown in FIG. 2, the inside surface of the wall portions 18,22, 48 and 50 are partially threaded such as shown at 58. However, thedepth of the threads into the thickness of the wall decreases in thedownwardly direction so that there is a gradual thread runout as shown.Because of this arrangement, it should be readily apparent that when aconstant diameter screw such as 36 or 38 is screwed into opening 32 or34, the interaction between the screws and the threads 58 act as a camthereby forcing the wall portions 18 and 48 or 22 and 50 to split awayfrom each other. To facilitate the turning of the screws, each screwincludes a square recess such as shown at 60 at the top thereof intowhich is inserted the square driver 62 of tool 64.

Referring again to FIG. 1, it should be noted that plug 40 and the lowerportion 45 of post 44 are also tapered to have a shape which issubstantially complementary to the configuration of the bore 52. Inaddition, the overall height of the plug 40 and the lower portion 45 ofthe post 44 are substantially equal to the overall height of the bore52. Thus, when plug 40, for example, is screwed into the bore 52, thetop of plug 40 lies at or below the top of the collar 30. In order tofacilitate screwing the plug 40 and post 44 into the bore 52, they areeach also provided with a square recess such as shown at 66 and 68.

A modified form of the implant shown in FIGS. 1 and 2 is illustrated inFIG. 3. It should be readily apparent that the implant shown in thisfigure is substantially identical to and functions in substantially thesame manner as the above described implant. The device, however, islarger and is, in essence, a combination of two of the above describeddevices placed end to end. Thus, the embodiment shown in FIG. 3 has alonger top wall 16', longer side walls 12' and 14' which are dividedinto five rather than three sections. Three of the five sections areconstructed similar to sections 18 and 22 and two of the sections, shownat 20' and 20", are constructed similar to section 20. Thus, theembodiment shown in FIG. 3 is adapted to hold two plugs such as plugs 40or two posts such as posts 44.

Another embodiment of the present invention is shown in FIG. 4. Again,this embodiment is similar to the embodiment shown in FIGS. 1 and 2 andincludes a substantially rectangularly portion having side walls 112 and114 which are also divided into three sections 118, 120 and 122. Themain difference between the embodiment shown in FIG. 4 and that shown inFIG. 1 is that this embodiment does not includes a top wall. Inaddition, the wall portions 118, 120 and 122 are integral with eachother.

As a result of the arrangement shown in FIG. 4, when screws 136 and 138are screwed downwardly into the screw threads formed on the surface ofthe walls 118, 148 and 122 and 150, the walls 118 and 148 and similarlythe walls 122 and 150 are cammed away from each other and fan outwardlyfrom the sides rather than from the bottoms as with the embodiment shownin FIG. 1.

Referring now to FIGS. 5 and 6, there is shown in these figures an evenfurther embodiment of the present invention. The implant 200 of thisembodiment includes an elongated rectangular body 210 having a pair ofspaced apart extensions 212 and 124 at the lower part thereof. Each ofthe extensions includes a plurality of holes such as 228 therethroughwhich are similar to and function in the same manner as the holes 28 ofthe embodiments shown in the previous figures. The inside opposing facesof 212 and 124 also include a plurality of recessed grooves such asshown at 226. For the reasons which will become clearer hereinafter, thedepth of the grooves 226 gradually decreases from the bottom of theimplant 200 to the top of the extensions 212 and 214.

A collar 230 extends upwardly from the top wall 216 of the implant 200.An elongated and relatively thin screw 236 is adapted to be insertedthrough the opening in the collar 230, down through the tapered bore 252in the portion 210 and into the opening between the extensions 212 and214. The screw 236 is screwed into a cylindrically shaped nut 238 whichis initially retained in the lower most groove 226 between theextensions 212 and 214. It should be readily apparent that when thescrew 236 is turned (by inserting tool 64 into the square recess 260)nut 238 moves upwardly. As the nut 238 moves upwardly, it passes fromone set of grooves 226 to the next higher one. Simultaneously, the nut238 acts as a cam thereby spreading the lower extensions 212 and 214away from each other. When the nut 238 has reached its desired point,i.e. when the degree of spreading has been reached, screw 236 is turnedin the opposite direction until it disengages nut 238 and can beremoved. The nut 238 remains in place since it is retained in thedesired groove and the extensions remain cammed apart.

It should be noted that the length, size and configuration of the bore252 is substantially equal to the bore 52 of the previous embodiments.Thus, with the screw 236 removed, a plug 40 or post 44 can be screwedinto the bore 252. The lower end of the bore 252 includes internalthreads 254 for this purpose.

The dental implants of the present invention are implanted in thefollowing manner. First, an incision is made in the gum ridge to exposethe bone structure 400 beneath. See FIGS. 8, 9 and 10. Thereafter, arectangular channel 402 of the desired shape is drilled. After theinitial drilling, the size and configuration of the channel 402 can bechecked using an initial gauge 300 such as shown in FIG. 7. Initialgauge 300 includes a lower rectangular portion 302 having aconfiguration substantially equal to the configuration of the implantbeing implanted but having dimensions slightly less than the dimensionsof the implant. Gauge 300 also includes an upwardly extending neck 304and a handle 306 attached to the top thereof. Located on the neck 304 isa marker groove 308 which functions as an indicator.

With the initial gauge 300, not only is the initial size and shape ofthe initial channel 402 checked, but the depth can also be checked byobserving whether the marker 308 is at its proper level at the top ofthe bone structure 400. If initial gauge 300 fits properly into place,then the channel 402 is enlarged and checked again with another gaugewhich may be similar to gauge 300 which has dimensions slightly largerthan the gauge 300. This second gauge may be a final gauge havingdimensions equal to the dimensions of the implant or it may be anotherintermediate gauge and the process may be repeated as desired.

Once the channel has been completed, such as shown in FIG. 8, an implantsuch as implant 10 is inserted therein and screws 36 and 38 are turnedcausing the walls 18 and 48 and 22 and 52 to flare outwardly against thewalls 404 and 406 of the channel thereby securely maintaining theimplant in place. With a plug 40 in place in the bore 52, the implant isallowed to remain for several weeks. During this time, the bone andother tissue grows through the holes 28 and over the top wall 16 of theimplant.

After the proper amount of bone and other tissue growth, the plug 40 isremoved and a post 44 is screwed into the threads 54 at the bottom ofthe bore 52. An artificial tooth is then secured to the post 44. Itshould be noted that since the post 44 is secured to the implant at apoint adjacent the bottom thereof, rather than near the top as is truewith most prior implants, there is less leverage on the implant andaccordingly, it is under less stress. This allows the use of eitherstraight or angled posts such as shown in FIG. 11.

The present invention may be embodied in other specific forms withoutdeparting from the spirit or essential attributes thereof and,accordingly, reference should be made to the appended claims, ratherthan to the foregoing specification as indicating the scope of theinvention.

We claim:
 1. A set of independent and unconnected gauges for use withpreparing a bone structure for implanting a dental implant, each of saidgauges in said set including: a first portion having a substantiallyrectangular configuration substantially equal to the configuration ofthe dental implant, the first portion on at least one of said gaugeshaving dimensions smaller than the dimensions of said implant and thefirst portion on at least one other of said gauges being substantiallyequal to the dimensions of said implant; and a second portion attachedto and extending upwardly from said first portion and including a markeron said second portion and a handle means for manually holding thegauge.